Riveting mandrel



July 5,1927. 1,634,521v

F. $TAPP RIVETING MANDREL Filed Deo. 28, 1.925

fi o

y seams Fatented July 5, 1927.

Fnn'nnnjicx'srarn OF DENVER, COLORADO.

RIVETING Application filed December This invention relates to improvements in riveting mandrels of the type employed ink the manufacture Ot tubular articles having riveted seams. Y

In the manufacture of pipes, cylindrical tanks, small boilers and similar articles, the

are often riveted. usually accomplished by placing a rivet on the upper surface of a. long mandrel. that is supported at one end and which extends outwardly from the .support iii the :t'orm ot a cantilever. vThe tubular member that is to beiiveted vis then passed over the mandrel and carefully lowered onto the rivet. li' the seam has already been drilled, it is then necessary for the operator to carefully lmove the pipe 'from one y'position to another in an ciiort to introduce the rivet into the hole; this Ais a. very tedious and diiiicult operation 'fro-r the reason that the rivet is concealed and rests loosely upon the mandrel. o It the rivet is moved, however slightly, in aA sidewise dii'ection, it will topple over, which means that the pipe will have to be removed and the rivet replaced after which another try must be made. It can readily be seen that the proper placing of the article to be riveted, so as to get the invisible rivet into the desired location is a diiticult task and it often happens that several minutes are required to place aV single rivet.

It is the object ot this invention to produce an apparatus ot this type that is so constructed that the article to be riveted .can be slipped over the mandrel bei'or'e any rivet is pnt into place thereon and which shall be provided rwith means for introducing the rivets into the same while the article is still in placeI over the mandrel, It is also an object oif'this invention to produce an article of this type thatr shall have means for ac` ourately indicating` the exact position of the rivet so that the operator can always tell the exact spot of the article that lies directly over the rivet.

The above, and other objects that may become apparent as the description proceeds, are attained by means that I will now describe in detail, reference for this purpose being had to the accompanying drawing in which the preferred embodiment of the invention has been illustrated and in which:

Fig. 1 is a top plan view of my improved device;

Fig. 2 i

s a side View of the invention, parts being breite:-

ii to better disclose the conrlfhis operation is I y l showing the manner of attaching the rivet es, i925, f seriai No. 77,984.

struction and pipe beii'ig'i'shownv in place about the mandrel; v v

Figr 3' is a section, toa somewhat enlarged scale, taken VOnline 3-3', Fig. 1;

Fig. l is afsection taken on line 4 4, Fig. 3;,and 1 5 is a detail view, partly in section,

to the feeding means. l

Numeral 1 indicates a support such .as the top ofA al workbench, The top of this bench isa convenient distance above the ioor. Secured to the bench 1 is my improved rivetirO' mandrel'which consists of a base 2 that isllastened to the bench 1 by means of bolts 3. Formed integral with the basey 2, oriigidly secured to it 1n some suitable way, v

is a cylindrical mandrel 4l, which may be Ot cast steel or other suitable material. This mandrel has been shown as of circular cross section, which -is, consid-ered preferable, but

anyl other cross sectional shape may be employed. It is, however, preferable to have thev upper surface of the mandrel slightly convex, The base 2 has a wall 5 extending vupwardly along its vfront edge and this wall has an opening 6 directly over the top of the mandrel 4. An upstanding ridge or support 7 extends rearwardly fromthe wall 5 and forms, in effect, a prolongation of the mandrel Il. A dovetail groove 8 extends rearwardly from the point 9, near the outer end of the mandrel l to the rear end of the support A strap. 10'Of steel, iron or other material is slidably mounted inthe groove 8 andlias Aoneend provided with a notch ll which is adapted to receive the shank v12 ofy a rivet. It will ,be noted that the end of the. strapl@ adjacent `the notch 11 yis 'cupped upwardly in the manner indicated ,bylllmeral 13 in Figs. 3 and 5 yso asto provide a recess Vfor receiving the head of the rivet. The inclined sides of the groove 8 terminate at 9 and from thence the bottom of the slot inclines upwardly in the manner indicated by numeral 14 in Fig. 3. The strap 10 has a stop 15 that is so placed as to engage the end of the upright 7 so as to limit the outward movement of the strap whereby the rivet can be positively located. `The end of the strap 10 opposite from the notch 11 has a portion 16 that is bent sopas to form a handle that can be grasped for moving the strap. The strap can be moved towards the right into a position like that shown in Fig. 5 in which posi.-

tion the rivet 12 can be introduced into the notch 11, after which the strap can be pushed towards the left until it reaches the position shown in Figs. 2 and 3, where the rivet will be quite firmly held in the lmanner shown. A pipe 17 can now be slipped over the mandrel t in the usual manner. It is evident that when t-he pipe 17 is in place, as shown in Fig. 2, that the rivet will be hidden and the operator cannot tell just where it is. To enable the operator to locate the exact position of the rivet when the pipe is in place, I have provided an arm 18 that is hinged so that. it can be swung about an axis indicated by numeral 19. A pin 2O is secured to the underside of the arm 18 and is so located that when this arm is in the position shown in Fig. 2, the point of this pin will be directly over the rivet 12. It is now evident that when the pipe 17 is in place and conceals the rivet, it is only necessary to swing the arm 18 down until the point of the pin 2O rests upon the pipe; this will then indicate the exact position of the rivet. If the material has been drilled and it is desired to insert a rivet into the hole, it is only necessary to bring the hole into position underneath the pin-20, when it will be directly over the rivet 12. In order to hold the arm 18 out of the way whilethe rivet is headed I have provided a latch which has beenillustrated as consisting of a short inclined arm 2l that is fastened. to the arm 18 near the hinge 19 and which cooperates with the sprinfy 22 to hold the arm in the position indicated by dotted lines in Fig. 2. After the rivet has been inserted into the opening` in the pipe, an assistant may withdraw the strap until it occupies the position shown in Fig` 5 and put another rivet in place. This rivet may be quickly moved to the position shown in Fig. 8, without removing the pipe. lith this apparatus no time is wasted in introducing the rivets into the holes provided for them or in locating the exact position of the rivet with respect to the pipe whereby a large amount of time can be saved on each operation.

It is understood that the device shown is illustrative only and is to be construed as such and not in a limiting sense.

I-Iaving now described the invention what is claimed as new is:

1. A device for use in riveting tubular articles comprising, in combination, a support, a mandrel secured at one end to said support and projecting outwardly therefrom, said mandrel having a dovetailed groove extending longitudinally thereof and located in its upper surface, a strap slidably mounted in said groove and having means at one end for holding a rivet, and a stop at the other end for determining the maximum distance that the strap can be moved in one direction whereby a rivet may be moved to a predetermined position, an indicator arm hingedly connected at one end to said support, said arm carrying a pin and being substantially straight beyond the hinge in the direction of the pin, the length of the said arm from the axis of its hinge to the p-in ybeing predetermined so that the rivet when the strap is extended to the maximum distance, is in alignment with the pin, and means for holding the indicator arm in the inoperative position.

2. In a riveting device, the combination of a support, a mandrel secured at one end to said support and projecting outwardly therefrom, said mandrel having a groove extending longitudinally thereof and iocated in its upper surface, a strap slidably mounted in said groove and having means at one end for holding a rivet, and a stop at the other end for determining the maximum distance that the strap can be moved in one direction whereby a rivet may be moved to a predetermined position, .an indicator arm hingedly connected at one end to said support, said arm carrying a pin, the length of said arm from the axis of its hinge to the pin being predetermined so that the rivet when the strap is extended to the maximum distance is in alignment with the pin. and resilient means for holding the 'indicator' arm in the inoperative position.

.In testimony whereof I ax my signature.

FREDERICK STAPP. 

